BSP50 Equivalent & Substitute Parts

Part Overview

The BSP50 is an NPN Darlington bipolar junction transistor manufactured by onsemi, designed for surface mount applications in the SOT-223-4 package. This device operates at a maximum collector-emitter voltage of 45 V with a collector current rating of 800 mA and maximum power dissipation of 1 W. The BSP50 is classified as obsolete, necessitating identification of equivalent and substitute components for ongoing design requirements and production continuity. Substitute parts must maintain functional compatibility within the specified electrical and mechanical parameters while considering current product availability and active manufacturing status.

Substiute Parts

BSP50

onsemiIn Stock: 29822BSP50 Datasheet

Current PartRFQ

BSP52T1G

onsemiIn Stock: 64289BSP52T1G Datasheet

DirectRFQ

BSP50,115

Nexperia USA Inc.In Stock: 1726BSP50,115 Datasheet

SimilarRFQ

FZT690BTA

Diodes IncorporatedIn Stock: 35045FZT690BTA Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the BSP50 are classified based on electrical parameter compatibility and package equivalence. The primary substitution criteria are:

Direct Substitution Criteria:

• Transistor Type: NPN - Darlington configuration
• Voltage Rating: Minimum 45 V collector-emitter breakdown voltage
• Current Rating: Minimum 800 mA collector current capacity
• Vce Saturation: 1.3 V @ 500µA, 500mA
• DC Current Gain (hFE): Minimum 2000 @ 500mA, 10V
• Package Compatibility: SOT-223 surface mount package (TO-261-4 or TO-261AA)
• RoHS Compliance: ROHS3 Compliant
• Moisture Sensitivity: MSL 1 (Unlimited)

Substitution Categories:

Direct Manufacturer Substitute: BSP52T1G meets or exceeds all electrical parameters with higher voltage (80 V) and current (1 A) ratings, maintaining identical saturation voltage and current gain specifications. Active product status ensures ongoing availability.

Similar Manufacturer Substitute: BSP50,115 (Nexperia USA Inc.) maintains identical voltage (45 V) and saturation characteristics with increased current capacity (1 A) and power rating (1.25 W). Active product status with automotive qualification (AEC-Q101) and transition frequency specification (200 MHz) provides enhanced performance margins.

Cross-Manufacturer Substitute: FZT690BTA (Diodes Incorporated) operates at identical voltage (45 V) with significantly higher current capacity (3 A) and power dissipation (2 W). This device is a standard NPN transistor rather than Darlington configuration, with lower DC current gain (150 @ 2A, 2V) and different saturation characteristics (500 mV @ 5mA, 1A).

Parameter Comparison

Engineering Selection Recommendations

BSP52T1G Selection Criteria: BSP52T1G is the primary direct substitute for BSP50 applications. This onsemi device maintains identical Darlington configuration, saturation voltage, and current gain specifications while providing enhanced voltage (80 V) and current (1 A) ratings. Active product status ensures supply chain continuity. The extended lower operating temperature limit (-65°C versus -55°C) provides additional thermal margin. Selection is appropriate for applications requiring direct parameter compatibility with improved performance headroom.

BSP50,115 Selection Criteria: BSP50,115 (Nexperia USA Inc.) serves as an alternative substitute maintaining identical voltage and saturation characteristics. Active product status with AEC-Q101 automotive qualification supports applications requiring automotive-grade components. The specified transition frequency (200 MHz) and increased power rating (1.25 W) accommodate higher-speed switching applications. This device is suitable for designs requiring automotive compliance or enhanced frequency performance within the 45 V voltage class.

FZT690BTA Selection Criteria: FZT690BTA represents a cross-manufacturer option with significantly different electrical characteristics. This standard NPN transistor (not Darlington) operates at identical 45 V voltage with substantially higher current capacity (3 A) and power dissipation (2 W). The lower DC current gain (150 @ 2A, 2V) and different saturation voltage (500 mV @ 5mA, 1A) indicate this device is suitable only for applications where Darlington characteristics are not required and where the circuit design accommodates the different gain and saturation properties. Active product status and broad availability support applications requiring high current capability at 45 V.

Frequently Asked Questions (FAQ)

Q: Can BSP52T1G directly replace BSP50 in existing designs?

A: BSP52T1G is electrically compatible with BSP50 for applications operating within the BSP50 specifications. The higher voltage rating (80 V versus 45 V) and current capacity (1 A versus 800 mA) provide performance margin. Identical saturation voltage and current gain ensure functional equivalence. PCB layout and thermal management remain unchanged due to identical SOT-223 package geometry.

Q: What is the primary difference between BSP50,115 and BSP52T1G?

A: BSP50,115 maintains the original 45 V voltage rating of BSP50, while BSP52T1G increases this to 80 V. Both devices share identical saturation voltage and current gain specifications. BSP50,115 includes automotive qualification (AEC-Q101) and specified transition frequency (200 MHz), making it suitable for automotive applications. BSP52T1G offers higher voltage headroom for general industrial applications.

Q: Is FZT690BTA suitable as a BSP50 replacement?

A: FZT690BTA operates at identical 45 V voltage but differs fundamentally in transistor type (standard NPN versus Darlington). The significantly lower DC current gain (150 versus 2000) and different saturation characteristics (500 mV versus 1.3 V) require circuit redesign. This device is appropriate only for applications where Darlington characteristics are not required and where the circuit accommodates the different electrical properties.

Q: Are all substitute parts available in the same package?

A: All substitute parts use SOT-223 surface mount packages (TO-261-4 or TO-261AA case styles). BSP50 specifies SOT-223-4, BSP52T1G uses SOT-223 (TO-261), BSP50,115 uses SOT-223, and FZT690BTA uses SOT-223-3. These package variants are mechanically compatible with identical pin spacing and PCB footprints, allowing direct board-level substitution without layout modification.

Q: What compliance certifications apply to all substitute parts?

A: All substitute parts maintain ROHS3 compliance and MSL 1 (Unlimited) moisture sensitivity rating, matching the original BSP50 specifications. BSP50,115 includes additional AEC-Q101 automotive qualification. All devices are REACH Unaffected and carry EAR99 ECCN classification.

Q: Which substitute offers the best performance margin for 45 V applications?

A: BSP50,115 maintains the original 45 V voltage specification while providing increased current capacity (1 A versus 800 mA) and power rating (1.25 W versus 1 W). The specified transition frequency (200 MHz) supports higher-speed switching. This device offers optimal performance margin while preserving the original voltage class and Darlington characteristics.

Q: Can BSP52T1G be used in applications with voltage constraints below 80 V?

A: BSP52T1G operates correctly in applications with voltage requirements up to 80 V. The higher voltage rating does not restrict operation at lower voltages. For applications with strict 45 V voltage specifications, BSP50,115 maintains the original voltage rating while providing equivalent or superior performance.